목적: 본 연구는 안경원 및 안과의 시력 검사실의 다양한 조도가 피검자의 동공 크기 변화에 미치는 영향을 평가하고 자 하였다. 또한 이러한 동공 크기 변화가 이색검사를 이용한 굴절검사 결과에 미치는 영향을 분석하여 시력 검사실의 적정 조도 수준을 모색하고자 하였다. 방법 : 안질환 관련 수술 경험이 없고 시력과 동공에 영향을 줄 수 있는 전신질환 및 안질환이 없는 성인을 대상 으로 기본 검사(색각 검사, 동공 기능)를 진행하였다. 완전교정 자각식 굴절검사 후에 단안 이색검사를 진행하였다. 4단계의 조도(10, 50, 300, 630 lx)를 설정하고 각 조도에서 적응 후 동공 크기를 측정하였다. 굴절이상 변화는 적 록 차트를 사용하여 교정했으며, 변화가 있는 경우 0.12 D의 구면 렌즈를 추가하여 굴절이상 변화량을 정량화하였 다. 결과 : 각 조도 단계별 굴절이상 값(이색검사 값)의 변화량은 유의한 차이가 있었다(F=37.61, p=0.000*). 뿐만 아니라 동공 크기 증가에 따른 굴절이상 값의 변화량 사이에 유의한 양의 상관관계가 있었다(r=0.178, p=0.006**). 그리고 동공 크기가 증가할수록 굴절이상 값의 변화량도 유의하게 증가하는 것으로 나타났 다(p=0.006**). 특히 어두운 조도 환경(10 lx)에서 밝은 조도 환경으로 변환(630 lx) 시 굴절이상 값의 변화는 +0.24 D 이상으로 가장 두드러졌다. 결론 : 시력 검사실의 조도 변화는 피검자의 동공 크기 변화를 유발하며, 이는 굴절이상 값(이색검사 값)의 변화 에 영향을 미치는 주요 요인 중 하나임을 확인하였다. 따라서 실제 안경 착용자가 일상생활을 영위하는 환경의 조 도는 주로 명소시 상태에 해당하므로 안정적이고 최적의 시력 교정효과를 제공하기 위해서는 최소 50 lx 이상의 조 도 상태에서 최종 굴절이상 값의 결과를 확인하는 것이 적합할 것으로 사료된다.

This study analyzed the selectivity of cylindrical net pot for the swimming crab (Charybdis japonica) using the SELECT model with a normal function. Data were obtained from four sea trials employing six mesh sizes (20.2, 27.6, 33.7, 37.9, 50.5, and 65.0 mm). The carapace length corresponding to the maximum catch in each mesh size ranged from 32.6 to 36.7 mm, whereas larger meshes of 50.5 mm and 65.0 mm exhibited peaks at 50.3 - 52.3 mm. This result clearly demonstrated that the size composition of the catch varied with increasing mesh size. The 50% retention carapace length (L50) ranged from 25.2 to 47.8 mm. When comparing fishing performance, smaller mesh pots generally yielded higher catches relative to the 20.2 mm reference pot. A comparison between the legal mesh size of 33.7 mm (nominal 35 mm) and the adjacent 37.9 mm mesh revealed that a 4 mm increase in mesh size significantly raised the proportion of crabs larger than 38 mm carapace length. Based on the minimum size at first maturity (28.86 mm), the optimal mesh size of the pot was estimated to be 35.59 mm. However, more precise sea trials and analyses are required to obtain reliable results. The findings also indicate that changes in mesh size have a clear influence on the size composition of swimming crab catches, suggesting that the correlation between mesh size and catch characteristics must be carefully considered to ensure sustainable resource management.

산림지역에서 강우는 수관층을 통과하면서 입자의 크기와 낙하 속도가 변화하게 되며, 이로 인해 수관통과우는 임외우와는 다른 물리적 특성을 나타낸다. 이러한 특성은 산림 내 토양침식 과정에 영향을 미칠 수 있으므로 수관통과우 의 특성에 대해 명확히 이해할 필요가 있다. 본 연구는 광학우적계의 관측 자료를 이용하여 임외우와 수관통과우의 강우입자 크기 분포 및 운동에너지를 비교ㆍ분석하였다. 이를 위해 강원대학교 춘천캠퍼스 내 잣나무림, 참나무림 및 공개지에 각각 1대씩 총 3대의 광학우적계를 설치하여 데이터를 수집하였다. 분석 결과, 중앙부피직경(D50, 평균±표 준편차)은 착엽기의 참나무림(4.20±0.61mm), 잣나무림(3.68±1.04mm) 및 낙엽기의 참나무림(2.32±0.45mm)의 수관통 과우의 순으로, 모두 임외우(1.98±0.76mm)보다 큰 것으로 나타났다. 강우입자의 직경별 부피비는 모든 임분의 수관통 과우가 약 3.0~3.5mm 이상의 직경에서 임외우보다 더 크게 나타났다. 강우운동에너지는 강우입자의 크기 분포와 유사한 경향을 보이며, 동일한 강우강도 대비 착엽기의 참나무림, 잣나무림, 낙엽기의 참나무림 및 임외우의 순서로 크게 나타났다. 이러한 결과는 수관통과우가 잎과 가지에서의 비산과 집적으로 인해 임외우와는 다른 강우입자 크기 분포를 보이며, 임지에 더 강한 운동에너지를 전달할 수 있음을 시사한다. 따라서 산림에서 발생하는 토양침식의 예측 정확도의 제고를 위해 산림의 임분구조에 따른 수관통과우의 입자 분포 특성에 대한 이해가 중요하다고 판단된다.

The recent development of small modular reactors (SMRs) and the adoption of higher-enrichment fuels have intensified the need for advanced burnable absorbers to ensure effective reactivity control and extended fuel cycles. Among various designs, UO2 fuels with high Gd2O3 (gadolinium oxide) content provide notable benefits; in particular, they are compatible with established fabrication methods for burnable absorber fuels. However, achieving a homogeneous dispersion of Gd2O3 at high loading levels remains challenging, and the frequent occurrence of phase segregation and non-uniform microstructures can limit fuel reliability and performance. Overcoming these limitations requires an understanding of the powder characteristics and mixing behaviors during fabrication. In this study, we investigate the effects of the initial particle size and mixing method of UO2 and Gd2O3 powders on the microstructure and mixing homogeneity of high-Gd2O3-content fuels. The findings indicate that both the mixing method and the preparation state of the starting powders significantly affect the resulting microstructure and mixing uniformity.

This study determined the appropriate pressure for high pressure shucking of oysters (Magallana gigas) according to size categories. One-year and two-year-old oysters harvested from Yeosu and Tongyeong coastal areas were subjected to high pressure treatments with pressure ranging from 180 to 240 MPa and holding times of 0 to 420 seconds. Results demonstrated that 100% shucking rates were achieved at 220 MPa with 120-180 seconds holding time regardless of harvest time and production area. K-means cluster analysis was used to classify oyster specimens into small, medium, and large size groups with mean shell heights of 69.0 mm, 86.6 mm, and 106.7 mm, respectively. The analysis revealed that shucking efficiency improved directly proportional to oyster size. However, the appropriate shucking pressures converged at approximately 220 MPa for all size groups, with small, medium, and large groups showing 218.9 MPa, 221.7 MPa, and 220.6 MPa, respectively, and no significant differences among groups. These findings suggest that the appropriate pressure for high pressure shucking processes be approximately 220 MPa regardless of harvest time and production area, providing foundational data for potential automation of oyster shucking processes.

In this study, we analyzed the structural and mechanical properties of aluminum foams fabricated using aluminum powders of varying sizes and mixtures. The effects of sintering and pore structure at each size on the integrity and mechanical properties of the foams were investigated. Structural characteristics were examined using scanning electron microscopy and micro–computed tomography, while mechanical properties were evaluated through compression testing. The experimental results demonstrated that smaller powder sizes improved foam integrity, reduced porosity and pore size, and resulted in thinner cell walls. In combination, these effects increased compressive strength as the powder size decreased. The findings of this study contribute to the understanding and improvement of the mechanical properties of aluminum foams and highlight their potential for use in a wide range of applications.

분리막 기술은 에너지 효율성과 연속공정 구성의 이점을 지니고 있으나, 소재 자체의 열역학적 선택도 한계로 인 해 유사 물질 간의 정밀 분리에 제약이 있다. 본 총설에서는 entrainer-assisted membrane separation (EMS) 전략을 통해 크기 공비(size-azeotrope) 난제를 공정 기반으로 극복하는 방안을 고찰한다. Ni/Na, Li/Na 등 혼합계 및 이온교환계에서의 실제 적 용 사례를 중심으로 EMS 전략의 작동 원리, 공정 설계의 유연성, 소재 재사용성과 확장 가능성을 정리하였으며, 향후 기술 적용을 위한 과제와 소재–공정 통합 설계 방향을 제안하였다.

This study analyzed the structural characteristics and influencing factors of fish assemblages according to lake size (small, medium, large) based on fish survey data from 90 lakes designated under the National Aquatic Ecosystem Health Monitoring Program in Korea. From surveys conducted between 2022 and 2024, a total of 107 fish species belonging to 32 families were recorded. The dominant species was the bluegill (Lepomis macrochirus, relative abundance [RA]: 21.2%), followed by Hemiculter eigenmanni as the subdominant species (RA: 13.6%). Statistical analysis based on lake size revealed significant differences across eight ecological indicators including species richness, abundance, diversity, evenness, richness, dominance, number of endemic species, and number of exotic species according to lake size. These indicators tended to increase with lake size. While this pattern may be initially attributed to positive factors associated with larger lakes, such as greater habitat heterogeneity and food resource diversity, it is considered that the primary factor influencing these results is the difference in the number of sampling sites per lake. Since sampling sites were designated based on the national water quality monitoring network, they are considered representative of each lake’s environmental conditions. Bray-Curtis similarity and SIMPER analyses identified patterns in assemblage similarity and the key contributing species for each size group. This study provides empirical evidence that demonstrates the influence of lake size on fish assemblage composition and structure and highlights the necessity of incorporating lake size and typology into fish-based assessments of lentic ecosystem health.

Springtails (class Collembola) play a crucial role in soil ecosystems. They are commonly used as standard species in soil toxicity assessments. According to the ISO 11267 guidelines established by the International Organization for Standardization (ISO), Allonychiurus kimi uses adult survival and juvenile production as toxicity assessment endpoint. Conventional toxicity assessment methods require manually counting adults and larvae under a microscope after experiments, which is time-consuming and laborintensive. To overcome these limitations, this study developed a model using YOLOv8 to detect and count both adults and juveniles of A. kimi. An AI model was trained using a training dataset and evaluated using a validation dataset. Both training and validation datasets used for AI model were created by picturing plate images that included adults and larvae. Statistical comparison of validation dataset showed no significant difference between manual and automatic counts. Additionally, the model achieved high accuracies (Precision=1.0, Recall=0.95 for adults; Precision=0.95, Recall=0.83 for juveniles). This indicates that the model can successfully detect objects. Additionally, the system can automatically measure body areas of individuals, enabling more detailed assessments related to growth and development. Therefore, this study establishes that AI-based counting methods in toxicity assessments with offer high levels of accuracy and efficiency can effectively replace traditional manual counting methods. This method significantly enhances the efficiency of large-scale toxicity evaluations while reducing researcher workload.

This study investigates differences in Chinese receptive vocabulary size and perceived lexical difficulty among three groups of Korean university students: Chinese majors, liberal arts students studying Chinese, and students with no formal exposure to Chinese. A total of 156 participants completed a 47-item Vocabulary Level Test (VLT) based on HSK levels 1–5. Data were analyzed using one-way ANOVA and Item Response Theory (IRT). The results revealed significant group differences: Chinese majors demonstrated the highest lexical competence, followed by liberal arts students and then non-learners. Notably, non-learners achieved a mean accuracy rate of 38.30%, likely due to the influence of Sino-Korean cognates. IRT analysis further indicated that Chinese majors perceived the items as relatively “easy,” liberal arts students as “difficult,” and non-learners as “very difficult.” These findings underscore the critical role of linguistic and cultural familiarity—particularly knowledge of Chinese characters—in facilitating vocabulary comprehension. The study advocates for differentiated instructional strategies tailored to learners’ backgrounds and calls for future research involving students from non-Sinographic language backgrounds to enhance the generalizability of the findings.

This study evaluated catch selectivity differences between sea pike (Sphyraena japonica) and Spanish mackerel (Scomberomorus niphonius) using a modified codend with square mesh side panels in bottom trawl. Sea trials were conducted with the covered codend technique widely used to estimate codend selectivity curves at the coastal sea of Yokji-do, Gyeongsangnam-do, from December 2024 to January 2025. Selectivity curves were fitted using a B-spline model for sea pike and a probit model for spanish mackerel. The estimated 50% retention lengths ( ) were 26.88 cm for sea pike and 42.92 cm for Spanish mackerel, with selection ranges () of 2.42 cm and 10.76 cm, respectively. Spanish mackerel was shown the broader and more gradual selectivity curve, while sea pike showed steeper selectivity. This study found that selectivity changes depending on the change in the net structure of the trawl tip. In addition, a difference in selectivity was observed for two species with different morphological characteristics.